perf(baseline): 1000-frame steady-state capture with quad-proxy draw calls + JSON sink

HellionChat/SelfTests/PerformanceBaselineLog.cs

@@ -0,0 +1,68 @@
+using System.Globalization;
+using System.IO;
+
+namespace HellionChat.SelfTests;
+
+// Disk sink for the B5 performance baseline. Kept separate from the SelfTest
+// step so the per-frame hot path never references file IO. Writes one
+// perf-baseline.json into the plugin ConfigDirectory, atomically (tmp + move)
+// like ThemeRegistry's theme writer, so a mid-write crash leaves either the
+// old file or the new file, never a half JSON. Field names track §7.5:
+// steady-state Draw cost (avg/max ms), the quad-proxy draw-call count
+// (avg/max), and frame delta (avg/max). First-frame-HITCH is read off
+// drawMs max/avg by the human author, platform-annotated in the notes.
+internal static class PerformanceBaselineLog
+{
+    internal static string Write(
+        double avgDrawMs,
+        double maxDrawMs,
+        double avgDrawCallsProxy,
+        double maxDrawCallsProxy,
+        double avgDeltaMs,
+        double maxDeltaMs,
+        int frames
+    )
+    {
+        var targetPath = Path.Join(Plugin.Interface.ConfigDirectory.FullName, "perf-baseline.json");
+
+        var json =
+            "{\n"
+            + $"  \"frames\": {frames},\n"
+            + $"  \"avgDrawMs\": {Fmt(avgDrawMs)},\n"
+            + $"  \"maxDrawMs\": {Fmt(maxDrawMs)},\n"
+            + $"  \"avgDrawCallsProxy\": {Fmt(avgDrawCallsProxy)},\n"
+            + $"  \"maxDrawCallsProxy\": {Fmt(maxDrawCallsProxy)},\n"
+            + $"  \"avgDeltaMs\": {Fmt(avgDeltaMs)},\n"
+            + $"  \"maxDeltaMs\": {Fmt(maxDeltaMs)}\n"
+            + "}\n";
+
+        // Atomic replace — same volume rename is atomic on POSIX and Windows.
+        var tmpPath = targetPath + ".tmp";
+        File.WriteAllText(tmpPath, json);
+        try
+        {
+            File.Move(tmpPath, targetPath, overwrite: true);
+        }
+        catch
+        {
+            // Avoid .tmp litter if Move fails (target locked).
+            try
+            {
+                File.Delete(tmpPath);
+            }
+            catch
+            {
+                // best effort
+            }
+
+            throw;
+        }
+
+        return targetPath;
+    }
+
+    private static string Fmt(double value)
+    {
+        return value.ToString("F2", CultureInfo.InvariantCulture);
+    }
+}

HellionChat/SelfTests/PerformanceBaselineStep.cs

@@ -1,19 +1,42 @@
-using System.Diagnostics;
 using Dalamud.Bindings.ImGui;
 using Dalamud.Plugin.SelfTest;
 
 namespace HellionChat.SelfTests;
 
-// Optional metric capture. Walks one frame's ImGui IO counters and
+// Optional metric capture. Accumulates 1000 steady-state frames of ImGui IO
-// prints a single JSON block so the cycle-notes author can copy/paste
+// counters plus the plugin's full-Draw wall-time (Plugin.LastDrawMs, B5-1),
-// the snapshot without standing up a separate profiling harness.
+// then writes a single perf-baseline.json into the plugin ConfigDirectory so
-// Investigations themselves are deferred to the polish cycle — this
+// the cycle-notes author can copy the §7.5 figures without a separate
-// step only records, it never fails on threshold.
+// profiling harness. The step only records — it never fails on a threshold
+// (the budgets are evaluated by a human against the JSON, §7.5 "optional,
+// manual"). It returns Waiting until the sample window fills, mirroring the
+// per-frame poll idiom of ThemeSwitchSelfTestStep.
 internal sealed class PerformanceBaselineStep : ISelfTestStep
 {
+    // §7.5 steady-state window. 1000 frames ≈ 16s at 60fps, long enough to
+    // average out GC blips without making the manual step tedious.
+    private const int TargetFrames = 1000;
+
+    // Quad proxy: ImGui emits 4 vertices + 6 indices per quad, so vertices/6
+    // approximates the draw-quad count. NOT the real ImDrawData command count —
+    // the <500/frame budget is checked approximately (API-3).
+    private const int VerticesPerQuadProxy = 6;
+
+    private readonly Plugin _plugin;
+
+    private int _frames;
+    private ulong _lastFrameCount;
+    private double _drawMsSum;
+    private double _drawMsMax;
+    private long _vertexSum;
+    private long _vertexMax;
+    private double _deltaMsSum;
+    private double _deltaMsMax;
+    private string? _logPath;
+
     public PerformanceBaselineStep(Plugin plugin)
     {
-        _ = plugin;
+        _plugin = plugin;
     }
 
     public string Name => "Hellion Chat - Performance baseline capture";
@@ -21,25 +44,69 @@ internal sealed class PerformanceBaselineStep : ISelfTestStep
     public SelfTestStepResult RunStep()
     {
         var io = ImGui.GetIO();
-        var stopwatch = Stopwatch.StartNew();
-        // No actual probe — we just sample the counters that ImGui keeps
-        // updated each frame. Stopwatch is started so the JSON line
-        // includes a non-zero wall-time figure even when ImGui has not
-        // accumulated frame stats yet.
-        stopwatch.Stop();
 
+        // Count each real frame once. Without the FrameCount gate a step that
+        // is polled more than once per frame would inflate the sample count.
+        var frameCount = Plugin.Interface.UiBuilder.FrameCount;
+        if (frameCount != _lastFrameCount)
+        {
+            _lastFrameCount = frameCount;
+            _frames++;
+
+            var drawMs = _plugin.LastDrawMs;
+            _drawMsSum += drawMs;
+            if (drawMs > _drawMsMax)
+                _drawMsMax = drawMs;
+
+            long vertices = io.MetricsRenderVertices;
+            _vertexSum += vertices;
+            if (vertices > _vertexMax)
+                _vertexMax = vertices;
+
+            var deltaMs = io.DeltaTime * 1000f;
+            _deltaMsSum += deltaMs;
+            if (deltaMs > _deltaMsMax)
+                _deltaMsMax = deltaMs;
+        }
+
+        if (_frames < TargetFrames)
+        {
             ImGui.Text(
-            "{ "
+                $"Sampling steady-state… {_frames}/{TargetFrames} frames. "
-                + $"\"renderVertices\": {io.MetricsRenderVertices}, "
+                    + "Keep the chat window visible and idle."
-                + $"\"renderIndices\": {io.MetricsRenderIndices}, "
-                + $"\"renderWindows\": {io.MetricsRenderWindows}, "
-                + $"\"activeWindows\": {io.MetricsActiveWindows}, "
-                + $"\"deltaTimeMs\": {io.DeltaTime * 1000f:F2}, "
-                + $"\"sampleWallTimeMs\": {stopwatch.Elapsed.TotalMilliseconds:F2}"
-                + " }"
             );
+            return SelfTestStepResult.Waiting;
+        }
+
+        _logPath ??= WriteBaselineLog();
+        ImGui.Text($"Baseline captured ({TargetFrames} frames). Wrote: {_logPath}");
         return SelfTestStepResult.Pass;
     }
 
-    public void CleanUp() { }
+    public void CleanUp()
+    {
+        _frames = 0;
+        _lastFrameCount = 0;
+        _drawMsSum = 0;
+        _drawMsMax = 0;
+        _vertexSum = 0;
+        _vertexMax = 0;
+        _deltaMsSum = 0;
+        _deltaMsMax = 0;
+        _logPath = null;
+    }
+
+    private string WriteBaselineLog()
+    {
+        // Disk write happens here, never in the per-frame hot path.
+        return PerformanceBaselineLog.Write(
+            avgDrawMs: _drawMsSum / TargetFrames,
+            maxDrawMs: _drawMsMax,
+            avgDrawCallsProxy: _vertexSum / (double)TargetFrames / VerticesPerQuadProxy,
+            maxDrawCallsProxy: _vertexMax / (double)VerticesPerQuadProxy,
+            avgDeltaMs: _deltaMsSum / TargetFrames,
+            maxDeltaMs: _deltaMsMax,
+            frames: TargetFrames
+        );
+    }
 }